Studies from a diversity of prokaryotic and eukaryotic organisms suggest a gradual evolution of biochemical and physiological mechanisms and metabolic pathways. Despite different evolutionary pressures, proteins that regulate the cell cycle in yeast, plant, nematode, fly, rat, and man have common chemical or structural features and modulate the same general cellular activity. A comparison of gene sequences with known structure and/or function from one plant species, for example, Arabidopsis thaliana, with those from other plants, allows researchers to develop models for manipulating a plant's traits and developing varieties with valuable properties.
A plant's traits may be controlled through a number of cellular processes. One important way to manipulate that control is through transcription factors proteins that influence the expression of a particular gene or sets of genes. Because transcription factors are key controlling elements of biological pathways, altering the expression levels of one or more transcription factors can change entire biological pathways in an organism. Strategies for manipulating a plant's biochemical, developmental, or phenotypic characteristics by altering a transcription factor expression can result in plants and crops with new and/or improved commercially valuable properties, including traits that improve yield under non-stressed conditions, or survival and yield during periods of abiotic stress. Examples of the latter include, for example, germination in cold conditions, and osmotic stresses such as desiccation, drought, excessive heat, and salt stress.
We have identified polynucleotides encoding transcription factors, including Arabidopsis sequences G1792, G1791, G1795, G30, and equivalogs listed in the Sequence Listing from a variety of other species, developed transgenic plants using some of these polynucleotides from diverse species, and analyzed the plants for their tolerance to disease and abiotic stress. In so doing, we have identified important polynucleotide and polypeptide sequences for producing commercially valuable plants and crops as well as the methods for making them and using them. Other aspects and embodiments of the invention are described below and can be derived from the teachings of this disclosure as a whole.